Insulating materials, such as silicon and its compounds, quartz, diamond, glass, ceramic or other materials are used more and more frequently to make micro-mechanical parts for the watch making industry, whether for fixed parts, such as plates or bridges, or for mobile parts forming, for example, part of the kinematic chain, or the regulating system, such as the balance spring, the balance or the escapement.
It has been observed, in particular on a balance spring that is totally isolated from the other parts for example by pinning up to the stud and bonding by means of a non-conductive adhesive, that the use of silicon has one drawback. Indeed, after a certain operating time, a certain number of coils located between the outer terminal curve and the inner terminal curve of the balance spring tend to adhere to the balance cock, which is necessarily detrimental to the isochronism of the regulating system. The same phenomenon can be observed with other parts made of silicon or another insulating material, which will also eventually have a detrimental effect on isochronism.